Refactored util.coffee into modular parts

util.coffee has become:
    constants.coffee: all of the constants
    logger.coffee:    prints logs, abstracts window.console on the Web
    util.coffee:      small utility functions that don't fit elsewhere
    classes.cofee:    base classes: `Id`, `HasSignals`, `Set`

All libraries should now be loaded via thier exports, eg:
    BAD:  imports.Mousetile.rect
    GOOD: imports.Mousetile.rect.exports